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Review is paper handout and overhead projector.
Following, microcontrollers, microprogramming and 64-bit.
A microcontroller may be a very small and inexpensive device.
The basic parts are Combinational Logic, logic gates, and some
type of stoarge, Sequential Logic.
A microcontroller may have Read Only Memory, ROM, that contains
a microprogam to run the microcontroller. Micro assemblers and
micro compilers may be used to generate the microprogram. The
microprogram is manufactured in the microcontroller.
This lecture also covers 64-bit machines.
A 64-bit architecture, by definition, has 64-bit integer registers.
Many computers have had 64-bit IEEE floating point for many years.
The 64-bit machines have been around for a while as the Alpha and
PowerPC yet have become popular for the desktop with the Intel and
AMD 64-bit machines.
Software has been dragging well behind computer architecture.
The chaos started in 1979 with the following "choices."
The full whitepaper www.1.org/whitepapers/64bit.html
My desire is to have the compiler, linker and operating system be ILP64.
All my code would work fine. I make no assumptions about word length.
I use sizeof(int) sizeof(size_t) etc. when absolutely needed.
On my 8GB computer I use a single array of over 4GB thus the subscripts
must be 64-bit. The only option, I know of, for gcc is -m64 and that
just gives LP64. Yuk! I have to change my source code and use "long"
everywhere in place of "int". If you get the idea that I am angry with
the compiler vendors, you are correct!
Here are sample programs and output to test for 64-bit capability in gcc:
Get sizeof on types and variables big.c
output from gcc -m64 big.out
malloc more than 4GB big_malloc.c
output from big_malloc_mac.out
The early 64-bit computers were:
DEC Alpha
DEC Alpha
IBM PowerPC
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